U.S. Pat. No. 4,411,110--Carey--describes a rain gutter construction said to offer particular advantage in preventing leaves, twigs, and other debris from entering the gutter and stopping rain flow into the connected downspouts. One limitation of such arrangement is the obviously clear showing of its restriction as a completed construction. That is, the gutter disclosed is only adapted for use where a new dwelling or building is to be constructed, or where a gutter is to be added to an existing dwelling or building, or where an existing gutter is to be removed and replaced with a new configuration. Clearly, there are millions-and-millions of dwellings and buildings where gutters already exist and where there is no intention of replacing them in the near future. It goes without saying that the teachings of this patent cannot there be put to use.
I have thought of modifying the disclosure of this patent, so as to construct a cover embodying its principles into an already existing gutter. However, this produced problems of its own--which, upon analysis and testing, were also found present in the design of U.S. Pat. No. 4,411,110 as a complete gutter construction. Thus, where it was the intention of this prior patent to employ narrow slots so as to keep leaves, rocks, twigs and nails from entering the gutter, such narrow slots themselves became clogged--especially when the installation was on a dwelling or building surrounded by pine trees or honey locust trees whose needles and sap tend to clog up the openings. In such situations, it has been found necessary to brush these slots clear periodically, sometimes up to three times per year.
Additional testing and analysis has also shown a further drawback in the prior teachings, as resulting from the relatively short length of the flaps established in the slots to guide and divert rainwater into the gutter. More specifically, such flaps must be critically angled even to operate as there described--but suffer the disadvantage that in colder weather, any rainwater guided along the flap by surface adhesion exhibited a tendency to freeze-up--where such "freeze-up" occurred, or where the flap was not angled properly, the guided rainwater did not completely fall into the trough, but fell by gravity, instead, along the facial board and sides of the structure.
Were this not bad enough, the situation grew worse when one tried to employ these features in fabricating a cover for an existing gutter. More particularly, in order to implement the teachings--and with a plurality of rows of interrupted slots to capture the rain--, in many installations it became necessary to lower the gutter so that the top surface of the cover could fit properly with the roof. Many of the average handymen who might try to install such an arrangement were found to lack the talent to lower these gutters properly--and such an undertaking was found to be completely beyond the ability and imagination of the average homeowner. In almost every instance, furthermore, investigation showed that the handyman or homeowner lacked the proper tools to begin such an undertaking, including the power screwdriver needed to secure the collar and rear walls of this earlier construction to the facial board (if intended to secure the construction by screws) and, most certainly, the tools needed to connect the cover to the existing gutter. As a result, it was found that any attempt to carry these patented teachings to a gutter installation that already had been erected required the skill of the professional installer, and at an increased cost.